Pumping apparatus



Patented Nov. l?, l.

UNITED vSTATES PATENT OFFICE.

LEROY 0. ARRINGDALE, OF'BGSTON, MASSACHUSETTS, ASSIGNOR TO EDSON MANU- FACTURING CORIORATION, F BGSTN, MASSACHUSETTS, A C()RPORATION OF -IVIASSACI-IUSETTS.

l PUMPING arraiuirus.

Application filed .Tanuary 10, 1924. Serial No. 685,463.

T 0 all whom t 'may Concern:

Be it known that I, LEROY O. AnnrNenALn, a citizen ofv the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Pumping Apparatus; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

'Ihe presentv invention relates to liquid pumping apparatus and more particularly to the reinforced flexible diaphragms employed in connection with such apparatus.

A well vknown type of hydraulic pump employs a flexible 'diaphragm in the general form of an annular ring which is clamped at its outer periphery to the stationary pump casing and at its inner periphery to the movable pumping head. The movement of the pumping head to opposite limits of its stroke imparts a like movement to the inner periphery of the diaphragm7 causing the latter to move through and beyond the plane of the outer periphery to opposite sides. yInthe usual practice, the relatively heavy and stiff reinforced diaphragm is molded so that the inner periphery of the diaphragm is normally positioned below the outer periphery corresponding to the lowermost position of the pumping head.'- Although this form of diaphragm has been' developed as the result of long experience, nevertheless the effective working life is relatively shortv and the diaphragms soon fail.r

It is the object of the present invention to provide an improved and relatively simple form of diaphragm which shall have a materially longer service period than diaphragms heretofore constructed.

lWith this object in view, the various features of the invention consist in certain novel features of construction, combinations and arrangements of parts hereinafter described and claimed, the advantages of which will be obvious to those skilled in the art from the following description.

In the accompanying drawings illustrating the preferred form of the invention, Fig. l represents a section in elevation of a conventional form of pump with the new diaphragm embodied therein; Fig. 2 is a detail illustrating a diaphragm embodying the present improvements partly in section; and.

Fig. 3 is a detail illustrating partly in seotion the conventional form of diaphragm nowin use.

As will be evident to those skilled in the art, the hydraulic pumpshown in the illustrated lembodiment of the invention comprises generally a hollow base member l0 having an intake connection l2 and a grooved face 14 for supporting the outer periphery of the diaphragm. The diaphragm Vindicated generally at 16 is clamped to the face le through an upper clamping member 18, the two members serving to rigidly clamp the outer periphery of the diaphragm and seal the space enclosed by the base member l0. The inner periphery of the diaphragm is connected to a movable pumping head having a lower portion 20 and a cooperating upper portion 22 which serve to clamp the inner portion of the diaphragm between them. A raised rib 24: formed upon the inner portion of the diaphragm cooperates with a pivoted valve member 26 to permit discharge of'water from the suction chamber upon the down stroke of the pumping head.

It will be evident from an inspection of Fig. lfthat the pumping head carrying the inner periphery of the diaphragm moves from thelowermost position vin which the diaphragm is 'shown in dot and dash lines tothe uppermost position indicated in a corresponding manner by dot and dash lines. In the lowermost and uppermost positions, the pumping head carrying the inner periphery of the diaphragm is farthest romoved from the outer edge of the diaphragm so that the diaphragm must be constructed with'sufiicient material to permit movement into the upper and lower positions of the head. In the conventional form of diaphragm shown at 30 in Fig. 3 the diaphragm is molded into a shape which corresponds with the lowermost position of the pumping` head so that at one limit of movement of the pumping head there is no distortion or fleXure of the diaphragm. Upon movement of the pumping head from the lowermost to theuppermost position, the

diaphragm is made to assume approximately the shape shown in dot and dash lines in Fig. 3. During the movement of the dialoo phragm between these two positions, however, and especially when passing through the mid position, corresponding to the plane ot the outer periphery of the diaphragm, the dipahragm is severely distorted, due. in part to the necessity ot moving the diaphragm through the relatively limited space at dilferent points between the inner and outer peripheries. in other words, the movement ot the inner periphery oi the diaphragm toward the outer periphery as the mid position is approached compelsa bucleling or folding oit the diaphragm, which puls a severe strain upon the material, especiall-,fv as this 'folding is a material. distortion Afrom the normal molded shape olf the diaphragm.

ircording to the present invention, the diaphragm molded in the mid position with an annular depending fold oi' siu'licient depth to provide the necessary material ttor the distention ol" the diaphragm during the nuovement ot the pumping head to itsouter most limits. lWith this` form of construction, the diaphragm when passing through the mid position, which normally represents the point of greatest distortion, is free from distortion and is subjected to only a gradual and cou'iparatively easy flexure during its movement in either direction trom the mid position. As indicatedI in Fig. l', the diaphragm is provided with an annular depending fold 32 positioned intermediate between the inner and outer peripheries of the diaphragm and lying between the opposite surfaces of the base member 10 and the movable pumping head, as clearly indicated in Fig. l. As the pumping head is moved from the mid position in either direction, the iold is gradually iiattened to distend the diaphragm and provide suiiicient material for the desired movement of the pumping head. The location ofthe expansion fold intermediate the inner andouter peripheriesof the diaphragm leaves substantially flat peripheral portions adjacent the movable and stationary portions of the pump, which are subjected to a minimum of movement and liexure.

The diaphragme ordinarily employed for this purpose are made of molded rubber, or

rubber composition, and are ordinarily provided with an inner reinforcement of one or more layers of fabric. As these dia phragms in addition average a foot or more in outer diameter and exceed a quarter of an inch in thickness it. will be quite evident that t-he severe buckling to which the usual shape is subjected in order to permit its passage through the restricted space in mid position causes rapid deterioration of the diaphragm, even when made of a high quality of rubber or rubber compound and strongly reinforced. The form of diaphragm illustrated and described, due to the more gradual change oit' shape and freedom from severe distortion, represents a very material advance from the standpoint of increased lite and serviceability.

lVhile it is preferred to employ the specific construction and arrangement of parts shown and described, it willbe understood that this construction and arrangement is not essential except so tar as specilied in the claim andmay be changed or modiied-V without departing from the broader features of the. invention. Y

The invention having been described, what is claimed is:

Pumping apparatus comprising a stationary pump housing, an annular diaphragm oi" rubber clamped at its outer periphery to the housing and molded with its inner and outer peripheries. in substantially the same plane and with an annular depending fold intermediate they inner and outer peripheries, a pumping head occupying the major portion of the space within the housing and clamped to the inner periphery of the annular diaphragm, the pumping head being movable within the housing throughV the plane of the diaphragm and to opposite sides thereof, the annular depending fold of the diaphragm lying in the regionot clearance between the housing and head when the latteris passing through they plane of the diaphragm and the fold providing sucient material to permit movement. of the inner periphery to the opposite limits of. movement of the head.

LEROY O. ARRINGDALE. 

